1. Field of the invention
This invention relates in general to treating a local soil to make it oleophillic and using the treated soil to minimize, consolidate, and clean up an oily spill.
It relates in particular to using silicone-type materials at ambient temperatures and atmospheric pressure as treating agents for naturally-occurring, locally-available soils, carrying out the treatment in locally available, commercial mixing equipment, spreading these treated soils on or adjacent to the oily spill-or where an oily spill might occur in the future--with locally-available commercial spreading equipment, allowing the oil to adsorb onto these soils, and then removing the oil-contaminated particles with locally-available, commercial earth-moving equipment.
2. Description of related art
When the spill of an oily substance, such as crude oil, a refined petroleum product, or other water-immiscible material occurs, it is extremely important to remove the substance as soon as possible to alleviate any harmful effects said materials might have on the environment. Delays can:
a) cause the volatile portion of the spill to vaporize, PA1 b) cause the spill to spread over vast distances, PA1 c) kill wildlife, PA1 d) contaminate beaches, waterways, groundwater, and other portions of the lithosphere. PA1 a) synthetic organic polymer particles PA1 b) chemically treated indigenous soils PA1 a) are acceptable in the environment, PA1 b) are efficacious in the application, PA1 c) are nonhazardous to inventory and ship, and PA1 d) have a low order of toxicity. PA1 a) methyl silicone chemicals degrade slowly in the environment to carbon dioxide and silica which are naturally-occurring materials, PA1 b) methyl silicones have an extremely low order of toxicity to humans and wildlife, PA1 c) the methyl silicone-treated soils have a long life in the environment. PA1 a) many of these same methyl silicone treatments may be carried out on many of the uncleaned, ungraded local soils present in the lithosphere, PA1 b) soils treated with permanent methyl silicone treatments will adsorb large amounts of oily spills, PA1 c) treatment techniques can be extremely simple and can be carried out in readily available commercial equipment, PA1 d) the treated soils can be spread on or adjacent to the oily spill, or at a site where an oily spill could occur at sometime in the future, using readily available commercial equipment. PA1 e) once the treated soils have adsorbed the oil, they can readily be separated from either water or the lithosphere with readily available commercial equipment and easily disposed of. PA1 a) Silylated Surfaces, D. E. Leyden and W. T. Collins, Gordon and Breach Publishers Inc, New York, (1980), PA1 b) Silanes, Surfaces, and Interfaces, D. E. Leyden and W. T. Collins, Gordon and Breach Publishers Inc, New York, (1986) PA1 a) None of the work was performed on dirty, unwashed, ungraded locally-available soils. PA1 b) None of the resulting particles was tested on or suggested for use in the environment for cleaning up oily spills. PA1 c) None of the treatments was applied in readily-available, portable, commercial mixing equipment. PA1 a) manufactured foamed particles created from a blend of solid and liquid alkali metal silicates are not naturally-occurring, locally-available soils. PA1 b) foamed particles created from a blend of solid and liquid alkali metal silicates cannot be manufactured in readily-available, portable, commercial mixing equipment. The process requires special manufacturing equipment to heat, crush, and classify the particles. PA1 a) they are a manufactured product, not a locally-available, naturally-occurring particle. PA1 b) they cannot be manufactured in readily-available, portable, commercial mixing equipment. The process requires special manufacturing equipment. PA1 c) the beads are not post-treated with a silicone-based surface treatment to make them oleophillic PA1 a) it is a manufactured product produced by burning chlorosilanes and collecting the resulting ash, not a locally-available, naturally-occurring particle. PA1 b) it cannot be manufactured in readily-available, portable, commercial mixing equipment. The process requires special manufacturing equipment. PA1 a) Organochlorosilanes having the general formula R.sub.n SiCl.sub.(4-n) where n is equal to 1, 2, or 3 and R is equal to H or any hydrocarbon group such as methyl, ethyl, or octadecyl. PA1 b) Organoalkoxysilanes having the general formula R'.sub.n Si(OR).sub.(4-n) where n is equal to 1, 2, or 3 and R and R' are equal to H or any hydrocarbon group such as methyl, ethyl, or octadecyl. PA1 c) Organoacetoxysilanes having the general formula R.sub.n Si(OOCCH.sub.3).sub.(4-n) where n is equal to 1, 2, or 3 and R is equal to any hydrocarbon group such as methyl, ethyl, or octadecyl. PA1 d) Methylhydrogensiloxane polymers having the general formula R.sub.3 SiO(CH.sub.3 SiHO).sub.n SiR.sub.3 where n is any value from 1 to 60 and R is equal to any hydrocarbon group such as methyl, ethyl, or octadecyl. PA1 e) Polydimethylsiloxane polymers having the general formula R.sub.3 SiO[(CH.sub.3).sub.2 SiO].sub.n SiR.sub.3 where n is any value from 0 to 500,000 and R is equal to any hydrocarbon or alkoxy group such as methyl, ethyl, or octadecyl, methoxy, or ethoxy. PA1 f) Alkali salts of methyl silicates such as sodium methyl siliconate and sodium dimethyl siliconate. PA1 g) Copolymers or mixtures of the above classes of materials such as mixed organochlorosilanes or dimethylmethylhydrogensiloxane copolymers.
When the volatile portion of the spill vaporizes, the air is contaminated and the higher-boiling portions of the substance are left. These high boilers are usually more difficult to remove from the environment.
When the spill spreads; more of the environment is damaged, mans ability to effectively clean up the spill is diminished, and the cost of cleanup rises dramatically.
When fish, mammals, or birds are contaminated by oily spills, they can be killed or their reproductive cycle can be disturbed. In the case of local endangered species, the entire species can be wiped out.
When beaches are contaminated, they are effectively rendered unfit for use by both man and wildlife. The same is true for waterways. In both cases, a valuable natural asset is lost for sometime, if not forever.
When other portions of the lithosphere, such as the ground, are contaminated, the oil can penetrate soil and seep into aquifers thereby contaminating groundwater supplies.
Almost any organic polymer which can be fabricated as a particle, particularly as a foamed-particle with a specific gravity less than one, and which has an oleophillic surface can effectively adsorb most oily pollutants.
Unfortunately, the majority of the soils which make up the earth's lithosphere are inorganic, oleophobic materials. They will not readily adsorb oily substances. However, they can be made oleophillic by treating them with chemicals.
Thus it is possible to use two types of particles to assist in containing an oily spill and cleaning it up, namely;
If synthetic organic polymer particles are used, they must be factory-produced ahead of time, transported in huge volumes to the site prior to the spill occurring, and stored in anticipation of a spill. After the spill has been contained, this huge volume of oil-contaminated particles must be disposed of in its entirety. Thus large costs are incurred which may or may not prove to have been necessary.
If naturally-occurring soils at or near the spill site are made oleophillic by chemically treating them, no action need be taken until a spill occurs; and after the spill has been cleaned up, the oil can be removed from the soil and the cleaned soil can be returned to the environment. This eliminates some very large costs. However, the chemicals must be carefully chosen in order to make certain that they:
It has been well known for over 50 years that clean, washed, graded, naturally-occurring siliceous materials containing surface hydroxy groups, such as silica sand and kaolinite-containing clays can be treated with various methyl-containing silicone materials to make the particles highly oleophillic. Some of these treatments are only temporary while others are permanent. A number of manufacturing plants exist around the world where such production takes place.
It is also widely known and documented that:
When these three facts are combined, methyl silicone treatments quickly become the first material of choice to evaluate for minimizing, consolidating, and cleaning up oily spills in an effective and economical manner.
It is the object of this invention to show:
3. Prior art
Methyl silicone treatment of siliceous particles
The process of treating siliceous particles with methyl silicones is well known and the body of work has been summarized in several major textbooks, two of which are:
The treatments discussed in this body of work fail to meet the objectives of this invention for one or more of the following reasons:
U.S. Pat. No. 3,843,306, Oct. 22, 1974, Whittington et al. In this patent, Whittington claims a manufactured foamed particle created from a blend of solid and liquid alkali metal silicates post treated with an oleophillic/hydrophobic agent used for the purpose of controlling oil pollution. The patent shows examples of using various silicone materials as the post treatment.
The foamed particle in this patent fails to meet the objectives of this invention because:
A product called "Seabeads", produced by Pittsburg-Corning, is cited as a competitive material in U.S. Pat. No. 3,843,306. (Col 2, lines 5-22). Seabeads fail to meet the objectives of this invention because:
A product called "silane-treated Cabo-O-Sil", produced by the Cabot Corporation is also cited as a competitive material in U.S. Pat. No. 3,843,306. Cab-O-Sil is characterized as a silane-treated silica. It fails to meet the objectives of this invention because:
Letter from Earth Sciences, Inc to US Geological Survey, Feb. 25, 1969, Douglas N. Stevens
This letter discloses Earth Sciences, Inc work with sand and chlorosilanes to manufacture an oleophillic particle from methyl silicone materials and locally-available, naturally-occurring soils. This was an initial disclosure of an early version of the invention cited in this patent application.
The treatment disclosed in this letter fails to meet the objectives of this invention because the treatment is carried out using a gaseous mixture of dichlorodimethylsilane and chlorotrimethylsilane. These particular compounds vaporize at temperatures in excess of 150.degree. F. As this temperature of vaporization is above normal ambient air temperature, the manufacturing process would have to include a step in which the chlorosilane mixture is heated to vaporize it. The invention cited in this application does not require this heating step.
It is also well-known that dichlorodimethylsilane and chlorotrimethylsilane hydrolyze readily at normal ambient temperatures in moist air releasing gaseous hydrogen chloride which can then further react with moisture to form hydrochloric acid. Thus, these materials are hazardous to ship and require a users to protect themselves against injury during particle treatment.
Article, California Oil World, Los Angeles, Calif., April 1969: This article, titled "Claim Oil Slick May Be Kept From Beaches", also discloses Earth Sciences, Inc work with sand and chlorosilanes to. manufacture an oleophillic particle from methyl silicone materials and locally-available, naturally-occurring soils. Again, this was an initial disclosure of an early version of the invention cited in this patent application.
The treatment disclosed in this article fails to meet the objectives of this invention because the treatment is carried out using the vapors of silicon compounds volatilized at 150.degree. F. As this temperature of vaporization is above normal ambient air temperature, the manufacturing process would have to include a step in which the chlorosilane mixture is heated to vaporize it. The invention cited in this application does not require this heating step.
Article, Denver Post Wed. Mar. 19, 1969: This article, titled "Sand May Clean Up Oil" and written by Gene Linberg, also discloses Earth Sciences, Inc work with sand and chlorosilanes to manufacture an oleophillic particle from methyl silicone materials and locally-available, naturally-occurring soils. Again, this was an initial disclosure of an early version of the invention cited in this patent application.
The treatment disclosed in this article fails to meet the objectives of this invention because the chemical nature of the treatment is not specified.